You see that, some get those lovely dual batteries, on-demand APU, F/O nosewheel, funny COM selector thingy, audio transfer switch equipped machines only as pre-owned
sounds as if you have one of my second-hand machines
PS Never raced or rallied...............................
If you PM me the current reg I'll be able to give you some history.
Regarding the 'Ingo' input, in my experience the fault was normally the standby Xfer, and nearly always on air starts, and ALWAYS cleared, so do not be 'confused'. Try my 'trick', as taught to me